Woooooooooiiiiiiii!!!! The biggest mistake you can make in the US is to compare land in the US to land in Kenya. Land in the US is so cheap. Every picture taken on that land looks fantastic, there are all the facilities you would want.
What these people are not telling you is that nobody completely owns any land in the US. The more desirable the location of the land the higher the PROPERTY TAX. If more and more people develop the area the county reevaluates the taxes accordingly. If you do not pay your property tax the county can sell the tax liens to other people who pay the tax and take over the property. It is a huge business. There are companies that do just that, buy up tax liens for people who cannot afford to pay their taxes and foreclose on the property.
It is crazy and totally legal. You buy a property for say $200,000. You get fired from your job or you fall sick and you fall behind on your taxes which have accumulated to say $20,000. Your tax lien is sold to someone who pays the county the $20,000 and now he kicks you out of the house which he now owns and sells it for $70,000. He has made $50,000 on his 20K investment while you have lost a 200K home because you could not pay 20K.